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<BODY><H2><a href="../contents.htm">Tcl8.6.11/Tk8.6.11 Documentation</a> <small>&gt;</small> <a href="contents.htm">Tcl Commands</a> <small>&gt;</small> time</H2>
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<H3><A NAME="M2">NAME</A></H3>
time &mdash; Time the execution of a script
<H3><A NAME="M3">SYNOPSIS</A></H3>
<B>time </B><I>script</I> ?<I>count</I>?<BR>
<H3><A NAME="M4">DESCRIPTION</A></H3>
This command will call the Tcl interpreter <I>count</I>
times to evaluate <I>script</I> (or once if <I>count</I> is not
specified).  It will then return a string of the form
<P>
<PRE><B>503.2 microseconds per iteration</B></PRE>
<P>
which indicates the average amount of time required per iteration,
in microseconds.
Time is measured in elapsed time, not CPU time.
<H3><A NAME="M5">EXAMPLE</A></H3>
Estimate how long it takes for a simple Tcl <B><A HREF="../TclCmd/for.htm">for</A></B> loop to count to
a thousand:
<P>
<PRE>time {
    for {set i 0} {$i&lt;1000} {incr i} {
        # empty body
    }
}</PRE>
<H3><A NAME="M6">SEE ALSO</A></H3>
<B><A HREF="../TclCmd/clock.htm">clock</A></B>
<H3><A NAME="M7">KEYWORDS</A></H3>
<A href="../Keywords/S.htm#script">script</A>, <A href="../Keywords/T.htm#time">time</A>
<div class="copy">Copyright &copy; 1993 The Regents of the University of California.
<BR>Copyright &copy; 1994-1996 Sun Microsystems, Inc.
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